This invention relates to loudspeakers, and is more particularly directed to loudspeaker enclosures that are collapsible to facilitate take down and set up, and which are also light-weight. The invention is specifically concerned with a portable speaker enclosure for performance or similar use that can replace bulky, and heavy rigid speaker enclosures.
Loudspeaker assemblies require an enclosure or chamber, which may or may not also include a vent or port, for the purpose of projecting the sound that is generated in the speaker. At the front of the enclosure is a front baffle, i.e., a board or plate on which the speaker or speakers are mounted. The baffle also has openings through which the sound is projected to radiate toward the audience. Typically, the enclosure has a large cabinet, with an interior volume of specific number of cubic inches so as to match the speaker's frequency response. The cabinet is usually very heavy, usually wood or equivalent, so that the cabinet does not vibrate or create undesirable buzzing or other noises. The inside of the cabinet is usually lined with plastic foam, fiber glass batt, or another acoustic insulating material. This absorbs unwanted vibrations, especially at higher frequencies, which can also cause undesirable distortion. A typical portable loudspeaker assembly with a rigid enclosure is discussed in U.S. Pat. No. 4,168,762.
Folding cabinets for speaker enclosures have been proposed, but these have not been satisfactory. The folding cabinets generally have hinged sides to permit them being set up and taken down so that they occupy less space during transport. However, these folding speaker enclosures are every bit as heavy as a conventional speaker enclosure and are equally as cumbersome once set up for use. Also, the hinged sides tend to rattle and produce unwanted noises during use, decreasing suitability of the speaker assembly for musical performers.
Ideally, a soft-sided, portable speaker enclosure would have the advantages of low weight and collapsibility, but would not have the disadvantages of the rigid enclosures mentioned above. However, because of the need for rigidity of the walls that define the acoustic chamber behind the speaker, no suitable soft-sided enclosure has been proposed to date.